A raincoat is indispensable in montaineering. A conventional raincoat used by mountain climbers is mostly a kind of windcoat, which can protect a person from wind, with a broad collar which can be pulled up to make up a head cover in case of rain for protecting his upper body and head from rain. Nevertheless, his lower body, or his legs and feet, cannot be covered by the windcoat, so he will become half wet and feel uncomfortable, or maybe grow sick. Besides, the windcoat generally has long sleeves which have to be folded up short because of sultry feeling caused by a long laborious climbing up a mountain.